The question of whether groups and clusters have their outskirts enriched at similar levels is of crucial importance. Besides the fact that outskirts represent by far the largest volume of these systems (hence the bulk of their metal masses), they are direct witnesses of freshly accreted gas through the gravitational potential of these systems and thus constitute a fossil record of the enrichment of these systems at their formation epoch. In fact, the (radially and azimuthally) uniform metallicity distribution measured in clusters outskirts constitutes by far our best evidence in favor of an "early-enrichment" scenario, in which supermassive black hole feedback played a fundamental role in ejecting and mixing freshly produced metals out of their galaxy hosts during or before their assembly into larger scale structures and the formation of their hot ICM, i.e. at \(z \gtrsim 2\) –3 [1]}, [2]}. Quite remarkably, this redshift range also corresponds to the peak of star formation activity [3]}, as well as to an epoch of enhanced AGN accretion and activity – not only at cosmic scale [4]} but also (and especially) in clusters and groups [5]}, [6]}, [7]}, naturally leading to the picture of their higher feedback to efficiently stir the freshly produced metals. Robust measurements revealing a uniform metal distribution in the IGrM as in the ICM will constitute decisive evidence towards this scenario and its "universal" 0.3 Solar value. On the contrary, significantly lower abundances measured in the IGrM outside \(\sim R_{500}\)  would challenge this scenario and would require to rethink our global picture of chemical enrichment at galactic scales and beyond. High resolution spectroscopy coupled to high throughput will be essential to bring our current measurements up to the required accuracy (Sect. ).
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